OF-807: Use IDN rules for S2S server names

Allow international domain names (per RFC 3490).

src/java/org/jivesoftware/util/StringUtils.java

@@ -20,9 +20,11 @@
 package org.jivesoftware.util;
 
 import java.io.UnsupportedEncodingException;
+import java.net.IDN;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.text.BreakIterator;
+import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -33,7 +35,6 @@ import java.util.Map;
 import java.util.Random;
 import java.util.StringTokenizer;
 import java.util.concurrent.ConcurrentHashMap;
-import java.util.regex.Pattern;
 
 import javax.mail.internet.AddressException;
 import javax.mail.internet.InternetAddress;
@@ -54,8 +55,6 @@ public class StringUtils {
     private static final char[] LT_ENCODE = "<".toCharArray();
     private static final char[] GT_ENCODE = ">".toCharArray();
     
-    private static final Pattern DOMAIN_NAME = Pattern.compile("^(?:[A-Za-z0-9][A-Za-z0-9\\-]{0,61}[A-Za-z0-9]|[A-Za-z0-9])$");
-
     private StringUtils() {
         // Not instantiable.
     }
@@ -1122,22 +1121,25 @@ public class StringUtils {
     }
     
     /**
-     * Returns true if the string passed in is a valid domain name
+     * Returns a valid domain name, possibly as an ACE-encoded IDN 
+     * (per <a href="http://www.ietf.org/rfc/rfc3490.txt">RFC 3490</a>).
      * 
      * @param domain Proposed domain name
-     * @return true if the string passed in is a valid domain name
+     * @return The validated domain name, possibly ACE-encoded
+     * @throws IllegalArgumentException The given domain name is not valid
      */
-    public static boolean isValidDomainName(String domain) {
-    	if (domain == null) {
-    		return false;
-    	}
-    	StringTokenizer parser = new StringTokenizer(domain, ".");
-    	while (parser.hasMoreTokens()) {
-    		if (!DOMAIN_NAME.matcher(parser.nextToken()).matches()) {
-    			return false;
-    		}
+    public static String validateDomainName(String domain) {
+    	if (domain == null || domain.trim().length() == 0) {
+    		throw new IllegalArgumentException("Domain name cannot be null or empty");
+    	}
+    	String result = IDN.toASCII(domain);
+		if (result.equals(domain)) {
+			// no conversion; validate again via USE_STD3_ASCII_RULES
+			IDN.toASCII(domain, IDN.USE_STD3_ASCII_RULES);
+		} else {
+    		Log.info(MessageFormat.format("Converted domain name: from '{0}' to '{1}'",  domain, result));
 		}
-    	return true;
+    	return result;
     }
     
     /**

src/test/java/org/jivesoftware/util/StringUtilsTest.java

 package org.jivesoftware.util;
 
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
 
 import org.junit.Test;
 
@@ -10,30 +10,38 @@ public class StringUtilsTest {
     @Test
     public void testValidDomainNames() {
     	
-        String domain = "www.mycompany.com";
-        assertTrue("Domain should be valid", StringUtils.isValidDomainName(domain));
+        assertValidDomainName("www.mycompany.com");
+        assertValidDomainName("www.my-company.com");
+        assertValidDomainName("abc.de");
+        assertValidDomainName("tronon.be", "xn--tronon-zua.be");
+        assertValidDomainName("bb.at", "xn--bb-eka.at");
 
-        domain = "www.my-company.com";
-        assertTrue("Domain should be valid", StringUtils.isValidDomainName(domain));
-    	
-        domain = "abc.de";
-        assertTrue("Domain should be valid", StringUtils.isValidDomainName(domain));
     }
     
     @Test
     public void testInvalidDomainNames() {
     	
-        String domain = "www.my_company.com";
-        assertFalse("Domain should not be valid", StringUtils.isValidDomainName(domain));
+        assertInvalidDomainName("www.my_company.com", "Contains non-LDH characters");
+        assertInvalidDomainName("www.-dash.com", "Has leading or trailing hyphen");
+        assertInvalidDomainName("www.dash-.com", "Has leading or trailing hyphen");
+        assertInvalidDomainName("abc.<test>.de", "Contains non-LDH characters");
 
-        domain = "www.-dash.com";
-        assertFalse("Domain should not be valid", StringUtils.isValidDomainName(domain));
+    }
 
-        domain = "www.dash-.com";
-        assertFalse("Domain should not be valid", StringUtils.isValidDomainName(domain));
+	private void assertValidDomainName(String domain) {
+		assertValidDomainName(domain, domain);
+    }
 
-        domain = "abc.<test>.de";
-        assertFalse("Domain should not be valid", StringUtils.isValidDomainName(domain));
+	private void assertValidDomainName(String domain, String expected) {
+        assertEquals("Domain should be valid: " + domain, expected, StringUtils.validateDomainName(domain));
     }
 
+	private void assertInvalidDomainName(String domain, String expectedCause) {
+		try {
+        	StringUtils.validateDomainName(domain);
+        	fail("Domain should not be valid: " + domain);
+        } catch (IllegalArgumentException iae) {
+        	assertEquals("Unexpected cause: " + iae.getMessage(), expectedCause, iae.getMessage());
+        }
+	}
 }

src/web/server2server-settings.jsp

@@ -136,8 +136,10 @@
     if (serverAllowed) {
         int intRemotePort = 0;
         // Validate params
-        if (domain == null || domain.trim().length() == 0 || !StringUtils.isValidDomainName(domain)) {
-            errors.put("domain","");
+        try {
+        	StringUtils.validateDomainName(domain);
+        } catch (IllegalArgumentException iae) {
+            errors.put("domain", "");
         }
         if (remotePort == null || remotePort.trim().length() == 0 ||  "0".equals(remotePort)) {
             errors.put("remotePort","");
@@ -164,8 +166,10 @@
 
     if (serverBlocked) {
         // Validate params
-        if (domain == null || domain.trim().length() == 0 || !StringUtils.isValidDomainName(domain)) {
-            errors.put("domain","");
+        try {
+        	StringUtils.validateDomainName(domain);
+        } catch (IllegalArgumentException iae) {
+            errors.put("domain", "");
         }
         // If no errors, continue:
         if (errors.isEmpty()) {